Reclaiming apparatus for pulp-mills.



C. B. CLARK. RBGLAIMING APPARATUS `EUR PULP MILLS` n v APBLIGTION FILED TUI-{6,1908. 927,951..l

Patented July 13, 1909.

Mln-$55555 if? 'l as Iused liquors are ultimately CHARLES B. CLARK, 0F BANGOR, MAINE.

` RECLAIMING APPARATUS FOR PULP-MILLS.

Specification o! Letters Patent; Application flied :une s, im. serial No. 131,069.

Patented July 13, 1909.

To all whom it may concern.:

Be it known that I, CHARLES B. CLARK, of county` of Penobscot and have invented a new and useful Improvement in Reclaiming Apparatus for Pulp- Mills, of which the following is a full, clear, and exact description, referencebeing had to the accompanyingdrawing, forming a part of this specification, in explaining its nature.

` My invention relates to an apparatus for reclaiming bisuliite liquor (and incidentally gas) discharged from the digestcrs during the digestive treatment of wood by the sulfite process to form wood pulp. The apparatus is especially adapted for carr in process of reclaiming the bisuliite di quor according to the process described in my lpending application for Letters Patent of ,the

United States filed June 12 1907, Serial N o. 378,507, in which liquor containing the constituents and extractives of the wood (which for the purposes of this application may be described as woody matter), are reclaimed by diluting the discharged liquorwith freshl bisulite liquor, which facilitates the separation of the woody matter contained the discharged or combined liquors and after which separation the woody matter may be removed when the y, discharged liquor thus clarified and regenerated by the fresh-'bisulfate liquor may be used for further digestive purposes. y

In the present a paratus my essential object is to rovide or the clarification of the discharged) liquor containing the woody mat- ,ter bydirecting it to a tank separate from the aimingV tankf in which the 4 stored for re-use, the discharged li uor being introduced into this auxiliaiy taiilk, maintained therein and diluted yrior to its entry into the reclaiming tank. he 'articularmanner in which this is done and t e essential advantages accruing so-called rec vtherefrom can better be understood and appreciated by describing the ap aratus.

In the drawing the improve apparatus is shown diagrammatically in plan. Referringto the drawingzr-A represents a digester. xtendinv from the top of the digester is an outlet ipe a throughjwhich' the gas land li uor disc arged from the digester are adapte( to pass. This ipe connects with a cooleral. Fromthc coo er the outlet-pipe `standpipe a3.

out the are preferably extended to connect.

is continued by a pipe a2 connecting with a From the standpi e a there extends upwardly a ipea whic connects with aistandpipe a5 t at communicatesiwith a reclaiming and storage tank A1 at a point preferably at or near its base. From the standpipe a3 preferably at or near the bottom thereofthere extends a pipe connection a which connects with an upright pipe a. Fromthe pipea7 thereextends a pipe as that connects with whatmay be termed a clarif ing tank A", the pipe a connecting with t e body ofthis` tank preferably at a oint some little` distance removed from t e .bottom thereof. From the tank Az there extends an outlet pipe a. extending' from the tank preferably ator near the bottom thereof and4 Branching from this pipe c is a pipe al` which runs downto connect with the bottom of the st'andpipe a5 and empties into the storage or reclaiming tank A1.` From the top of the clarifying tank A" there extends a pipe al" with which pipe the upright` pipes a?, a'

Connectingwith the clarifying tank A2 referably at a point at or near the bottom t pipe all. This ipe 0,12 connects with atank A3 containing resh bisuliite liquor and the pipe rovides means by which liquor is led out o the tank As into the clarifying tank A. The clarifying tank A2 it Will be observed is sov ereof is a 4ais preferably made with a contracting to or ead. i Proceeding ,from this portion o the tank is an outlet pipe a13 controlled by a valve al. The pipe a,13 empties into any suitable retort or receptacle als.

The aforesaiddescription is merel for the purpose of identifying the parts of t e apparatus. Reference will now be made more particularly to the specific arrangement` of them and their operationtending to the reclamation of theV sulfite liquor discharged` fromk the `digester. In the rst instance the li uor and gas; discharged from the digester wlill pass out ofthe digester by the wayof the outlet pipe a to pass through the cooler a. From the cooler the discharged liquor and gas will pass downwardly through the pipe a to enter the standpi e a3. At this point any free gas thatina e inthe liquor will rise and pass over, `by t e way'of the pipe a, into the standpipe a5, thence `down through this pipe into the reclaiming and storage tank'Al. The discharged liquor,

i' however, will vpass downwardly through the pipe a3 and thence out of this pipe bythe way of the connecting piped6 to en ter the uprlght pipe a7 and rise therein. This upright p ipe a7 it will be notedextends upwardly so highwith respect to the clarifying tank A2 that the liquor rising in the pipe a7 will flow out of it through the pipe a? and enter 'the body of' the clarifying tank A2 preferably at a point some little distance removed from the bottom of the tank. In order that the liquor may freely run into the clarifying tank irrespective of the amount of liquor therein, I prefer that the pipe as shall branch from the upright pipe a7 at a point relatively high with respect to the clarifying tank. In the apparatus shown the pipe a branches from the pipe a7 at a relative point just a little lower than the top of the clarifyinr tank. I prefer, also,'that the pipe a8 sha1 extend downward and enter the clarifying tank in a substantially horizontal position so that the liquor discharged through the pipe a8 into the clarifying tank may be disseminated throughout the body of the tank.

With respect to the outlet pipe a and pipe al@ branching therefrom to connect with t 1e reclaiming and storage tank A1, it-Will be observed that the pi ek am branches from the pipe a9 at a point re atively hi hwith respect to the clarifying tank, or in ot er words, at a point relatively commensurate with some point in the contracted portion or head of the clarifying tank. The reason for this is that as the discharged liquor fiows into the clarifying tank to rise therein the liquor will also rlse to a commensurate extent in the pipe a". Accordingly no liquor can fiow out of the clarifying tank until the liquor has risen so highm the pipe a as to reach the point where the pipe al@ branches therefrom when the li uor willflow out through vthis pipe. f'lhe e ect of this arrangement is that the clarifying tank will always be kept filled with li uor and preferably so filled that the top sur ace of theliquor in the tank will lie in the contracted top or head thereof.

The advantage of the afore-described arrangement in the first place is that by permitting the gas discharged from the digester to pass directly over into the storage tank and not into the clarifying tank, an excessive agitation of the liquor in the clarifying tank, which might prevent a rapid separation of the woody matter contained in the liquor, is prevented. It is desirable, however, that the liquor in the clarifying tank be subjected to some agitation to insure a rapid separation of the Woody matter and I find that rjust the proper amount of lagitation may be produced therein by the inflow of fresh liquor into the tank, this being preferably directed to flow into the tank in such manner as to cause the tank. Another advantage resides in the fact that the clarifying tank is continuously ke t filled with a large body of liquor. When tffe fresh bisulte liquor is introduced the tendency is for the liquor in the clarifying tank to clear from the bottom of the tank so that only clarified liquor Will escape from the tank by the Way of the outlet pipe and flow into the storage tank. By continuously maintaining a large quantity of liquor in the clarifying tank the woody matter will be continuously separating therein as discharged liquor from the digester is flowing into the tank and as this discharged liquor flows into the tank the liquor therein which has already become cleared at the bottom of the tank will fioW out of it into the storage tank, producing the effect in other words of a continuous operation Moreover as the storage tank contains only clarified liquor this liquor can be drawn from the storage tank regardless of the amount of liquor in the tank. y

The advantage of maintaining such an amount ofl liquor in the clarifying tank that the top surface of the liquor therein will come or lie in the contracted top or head of the tank resides in the fact that the surface tank will be made to occupy a position presenting less area in extent of surface but of greater depth than if the woody matter occupied a lposition presenting a larger surface area. ccordingly not only can the Woody matter be more conveniently drawn off by the way of the pipe a, but it is also unnecessary to wait until a large amount of the woody matter has accumulated before it can be drawn off Without the withdrawal also of p the sulfite liquor.

It will be understood that the woody matter is drawn off intermittently from the clarifying tank as it accumulates therein after its separation, by opening the valve a controlling the pipe (1,13 when the woody matter may Iass out of or be withdrawn from the tank. o prevent the contents of the clarifying tank from accidentally siphoning'out of it into the storage tank, which effect might be obtained unless some provision were made to prevent it, the pipe c is extended from the top of the clarifying tank to connect with the pipes a7, a9, thereby overcoming any tend-- ency to si honing. It will be understood also that t e liquor in the storage tank may be Withdrawn therefrom and discharged into the digester, as occasion may require, through the pipe al after the valve a controlling this pipe has first been opened, the liquor being discharged l'nto the digester by means of a' pump als.

Having thus fully described my invention,

I claim and desire to secure by Letters Patent of the United States y `1. In an apparatus of thecharacter specified, the combinationwith a digester, of a clarifying tank, astorage tank, means connectlng said digester with said clarifying tank whereby liquor discharfred from the digester may )ass into said clhrifying tank to be clarified of the woody matter contained therein by the separation of the woody matter from a body of said discharged liquor maintained in said clarifying tank, means whereby the Woody matter separated from theliquor insaid clarifying tank may be removed therefrom without disturbing'the main body of liquor therein, and means connecting said clarifying tank with said storage tank ywhereby clarified liquor therein may pass over and be discharged into said storage tank.

2. In an apparatus of the character specified, the combination with a digest'er, of a tank, means connecting the digester with said tank whereby liquor discharged from the digester may be directed to ass into said tank and become clarified of t e woody matter contained therein by the separation of the woody mattei' from a body of said discharged liquor maintained in said tank, means whereby other liquor may be directed into said tank for facilitating such separation, means whereby the woody matter may be removed from the tank after such separation without disturbing the `main body of liquor therein, and .means providing an outlet from said tank for directing clarified liquor out of the same.

3. In an ap aratus of the character specified, the com ination with a digester, of "a clarifying tanka storage tank, means connecting said digester with `said tanks arranged whereby gas discharged from the digester may pass into said storage tank and liquor discharged therefrom may pass into said clarifying tank to be clarified of the woody matter contained therein by the separation of said woody matter from a body of said discharged liquor, maintained in said clarifying tank, means whereby the'woody matter may be removed from the clarifying tank after such separation without disturbing the main body of liquor therein, and means connecting said clarifying tank with said storage tank whereby clarified liquor theein may be discharged into said storage tan 4. In an ap aratus of the character specified, the combination with a digester of a clarifying tank, means connecting said digcster with said clarifying tank whereby liquor discharged from the digester may pass into said clarifying tank tobe clarified of the woody mattei contained therein,` and means providing an outlet from said clarify.- ing tank whereby liquor clarified therein i digester ma vmeans is arranged whereby abody of liquor may becontinuously maintained in said tank. `f Vi l 5. In an ap ,aratus ofthe character specified,f the `com )ination with a digester of a clarifying tank, a `storage tank, means connecting said digester with said f clarifying tank whereby liquor discharged from the ass, into the clarifying tank to be clarified) of the woody matter contained therein,` and means` rovid ing an outlet from said clarifying tan and connecting with said storage tank, which means is arranged whereby clarified liquor in the clarifying tank may freely pass out of said tank into said storage tank and which means is arranged also whereby a body of liquor may continuously be maintained in said clarifying tank.

` 6. In an ap )aratus of the character specified, the combination with a digester of a clarifying tank, means connecting said dilfester with said clarifying tank whereby iquor discharged from the digester may ass into said clarifying tank to be clarified o the woody mat-ter contained therein, means for introducing a fresh liquor into said clarifying tank, and means providing an outlet from said tank through which the clarified liquor therein may be discharged, said means being arranged whereby a body of liquor may continuously be maintained in said tank and clarified liquor therein may pass out of said tank as liquor is discharged into the same.

7 In an ap aratus of the character specifled, the combination with a digester of a clarifying tank, means connecting said digester with said clarifying tank whereby liquor dlscharged from the digester may ass linto said clarifying tank to be clarified o the woody mattencontained therein, an outlet pipe from said clarifying tank adapted and arranged whereby a body of liquor may continuously be maintained in said tank, and means for preventing the li uor in said tank from'siphoning outwardly t rough said outlet pi e.

8. In an ap aratus of the character specified, the com ination with a digester of a clarifying tank having a contracted top or head, means connecting said digester with said clarifying tank whereby liquor discharged from the digester may pass into said clarifying tank to be clarified of the woody matter contained therein, means for introducing a fresh li uor into said tank, means providing an out et from said tank adapted and arranged whereby a body of li uor may continuously be maintained in saiitank to fill said tank up into `the contracted top or head thereof, and means providingvan out-let through said contracted top or head of the tank from the top suiface of the liquor contained therein.

.tank and said clanfying `tank `whereby gas discharged from the digestermay enter directly into the storage tank and liquor discharged from said igester may pass into said clarifying tank to `be clarified of the Woody matter contained therein by the 'separation of the Woody matter'from 7a body of `the discharged liquor-maintained in said clari ingtank, means whereby fresh liquor may` e -admitted into said clarifying tank,

means whereby Vthe woody matter after its separation may be removed from the clarifying tank and means roviding an' outlet from said clarifying tanlir at or near the bottomthereof and connecting with said'storage tank, said means being adapted and arranged whereby a body of liquor may continlously be maintained in said clarifying "tan e l V(1H-ARIES B. CLARK.

In the presence of CHAnLEs C. How, FRED-O. DOLLIYER. 

